I'd allow it if you have total control through the computer. Like smart chipped hardware in cyberpunk_________________"Eyes without life…sundered heads…piles of carcasses…these are pleasing words to me"
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That's the type of scenario I was thinking of but +4 seems a very powerful bonus.....maybe the character should suffer psychosomatic wounds if the ship is hit or something?

You can handle things like that with Fatigue.
Maybe an extended usage of the power becomes very tiring too and the pilot suffers one level of Fatigue for one hour after he has "locked off".
Although I wouldn’t let him get the +4 bonus for onboard weapon systems. If these systems have a built-in bonus (targeting system or something similar) than use that one instead._________________"So, how much Experience do I get for the bard?"

I wouldn't, or Interface becomes a universal modifier to anything that could plausibly have a computer control it. Instead I'd allow the Interface to give a +4 to the roll to interface with the computer that's controlling the system (whether it's a fighter jet, a nuclear power plant, or a coffee-maker), but all that does is allow you to use the relevant skill (Pilot, Repair, Common Knowledge) via the computer interface instead of by manually punching buttons and so forth. Certain systems might be built so you have to have the Interface power to "jack in" (no manual controls), but I'd still require that you use the relevant skill without any special bonus. If you want fly-by-thought fighters to be better than regular ones, give the bonus to the equipment, e.g. in the form of a Handling bonus.

. "...If you want fly-by-thought fighters to be better than regular ones, give the bonus to the equipment, e.g. in the form of a Handling bonus.

Or buy edges/powers/stats that can only be used when chipped in. For example normally you have a d4 agility but when you are plugged into vehicle or weapon system you have a d10 or even d12. I think NE has rules for this somewhere......

The power is being used in a Traveller (ish) conversion and I eventually went for the allowing Interface to be taken but only granting a blanket +2 to those systems that are equipped for computer control (so no shooting bonus for a rifle but you would get one for firing a starship laser)
The down side is that there is prejudice against cybernetics and revealing an Interface would subject the character to this

There is a second edge (Synchronised) that allows the +4 bonus and allows two computer controlled actions to be taken without a MAP
The Synchronised are constantly (and unconsciously) sending information back to the shadowy Controllers however and risk the implanting of “suggestions”